Exhaust Purification Device Capable of Performing Regeneration by Using Quick Combustion

ABSTRACT

An exhaust purification device for vehicles comprises a connection unit, a combustion unit, a buffer unit, a filtration unit, an emission unit, and a control unit. The connection unit is adapted to be connected to an exhaust pipe of a vehicle&#39;s engine. The combustion unit includes a main housing, a fuel-atomization nozzle, and an igniter. The nozzle and the igniter are arranged in an open-end container. The nozzle is connected to a fuel tank. An air pump is connected to the open-end container. The buffer unit is provided with a temperature sensor, an exhaust-buffering mask, and a fan. The filtration unit can remove the soot contained in the exhaust gas. The emission unit includes an L-shaped porous tail pipe being sealed with a porous cover. The control unit is electrically connected with the igniter, the fuel pump, the air pump, and the temperature sensor for controlling their operations.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an exhaust purification device that can be mounted to an exhaust pipe of a vehicle's engine to allow the accumulated soot to be quickly removed, so that the exhaust gas can be expelled more smoothly

DESCRIPTION OF THE PRIOR ART

For a diesel-engine vehicle, as the exhaust gas flow through a filter, the particulate matter or shoot contained in the exhaust gas can accumulate at the filter. After the vehicle has been used for a period of time, the accumulated particulate matter or soot can cause the filter to be plugged, thereby increasing the pressure in the exhaust pipe that mounts the filter. To solve the problem, the automobile industry employed a pressure sensor that can be installed in the exhaust pipe to detect the pneumatic pressure therein, so that the plugged condition of the filter can be obtained. With the pressure sensor detecting a high pressure, an engine management system of the vehicle can know the particulate matter accumulated in the filter has reached a noticeable amount. Under this condition, the engine management system can issue a signal that can increase the working temperature of the engine, so that the exhaust gas can consume the particulate matter to make the filter clean again, which is known as “filter regeneration”. However, since vehicles are often driven at low speeds on city streets, the working temperature of the engines cannot be increased to a level at which a regeneration process can be performed properly. To remove the accumulated particulate matter, the user has to request a service factory to burn the accumulated shoot up or replace the plugged filter with a new filter, and this is uneconomical and troublesome.

To solve the disadvantages of the conventional device, the applicant filed for a patent application (application Ser. No. 12/477,932) concerning a diesel-engine exhaust purifier. The primary feature of the application is that the purifier includes a burner system and a filter system, which are sequentially arranged from an exhaust pipe of a vehicle and controlled by a microcontroller. The burner system includes a first pressure sensor whereas the filter system includes a second pressure system. When the first pressure sensor detects a high pressure, the microcontroller can activate a fuel pump to supply fuel to a nozzle, and energize an igniter to ignite the fuel spray ejecting from the nozzle, to allow the burner system' temperature to reach about 400 degrees C. Then, the high-temperature exhaust gas can flow through the filter system to remove the accumulated soot. When the second pressure sensor detects a low pressure, which means the filter system has been restored to a clean state, the microcontroller can deactivate the fuel pump to stop the burning process.

Later, the applicant also filed for another patent application (application Ser. No. 13/596,025) concerning an exhaust purifier for solving the disadvantages of the conventional device. The primary feature of the application is that the exhaust purifier includes a burner system and an exhaust buffer-filter system, which are sequentially arranged from an exhaust pipe of a vehicle. There are multiple channels provided in the burner system. The exhaust gas can flow through the multiple channels of the burner system. An igniter of the burner system can ignite fine spray of fuel from a nozzle to start a burning. Then, the high-temperature exhaust gas can sequentially go past a buffer unit and a filter unit of the exhaust buffer-filter system. The buffer unit can reduce the flow speed of the exhaust gas. Also, the buffer unit allows the exhaust gas to be distributed more uniformly. Thereafter, the exhaust gas can flow through the filter unit to consume the accumulated soot therein, so that the exhaust gas expelled from the engine can flow through the purifier smoothly again.

However, the above application (application Ser. No. 13/596,025) is disadvantageous in that the exhaust gas expelled from the exhaust pipe may be hindered by the nozzle structure in the burner system, thereby causing an unsmooth exhaust emission and an incomplete combustion, or causing the engine to stall suddenly. Besides, the soot-removing speed and the heat-removing speed are not adequate. Thus, there is a need for further improvement.

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide an exhaust purification device for vehicles, which can solve the disadvantage of the conventional purification device that results from failure of increasing the working temperature of an engine.

Another object of the present invention is to provide an exhaust purification device that can make the emission of the exhaust gas smooth, and increase the speed of removing soot and the speed of removing heat.

To achieve the above objects, the exhaust purification device may comprise a connection unit, a combustion unit, a buffer unit, a filtration unit, an emission unit, a temperature sensor, and a control unit. The connection unit includes an inlet and an outlet, wherein the inlet is adapted to be connected to an exhaust pipe of a vehicle's engine. The combustion unit includes a main housing, a fuel-atomization nozzle, and an igniter. The main housing is connected to the outlet of the connection unit. The main housing defines a combustion chamber therein and is provided therein with a protective shell and an open-end container at a location that is not aligned with the outlet of the connection unit, wherein the open-end container is located within the protective shell and leaves a gap with the protective shell. The fuel-atomization nozzle and the igniter are arranged in the open-end container and face towards the combustion chamber. The fuel-atomization nozzle is connected to a fuel tank containing a fuel pump via a tube being provided with an electrical valve. An air pump is connected to the open-end container. The buffer unit includes a first buffer zone and a second buffer zone communicating with the first buffer zone, wherein the first buffer zone is connected to the main housing of the combustion unit and is provided therein with an exhaust-buffering mask near the main housing and a fan near the second buffer zone to allow the exhaust gas to go past the exhaust-buffering mask and then rotate the fan to enter the second buffer zone, whereby the exhaust gas can flow into the second buffer zone uniformly, thereby reducing the exhaust gas being transferred back to the combustion unit. The filtration unit is connected to the second buffer zone of the buffer unit for receiving the exhaust gas therefrom. The emission unit is connected to the filtration unit, wherein the emission unit includes an L-shaped tail pipe having a porous pipe wall and being sealed with a porous cover at its outlet. The temperature sensor is provided in the first buffer zone of the buffer unit for detecting temperature therein. The control unit is electrically connected with the igniter, the fuel pump of the fuel tank, the air pump, and the temperature sensor for controlling their operations.

The primary feature of the present invention is that the exhaust purification device includes a connection unit, a combustion unit, a buffer unit, a filtration unit, an emission unit, and a control unit, wherein the combustion unit is connected to an exhaust pipe of a vehicle's engine through the connection unit such that the exhaust gas expelled from the exhaust pipe would not be hindered by a nozzle provided in the combustion unit. Furthermore, an air pump is provided for the combustion unit to allow the fuel spray ejecting from the nozzle to be mixed with adequate air to achieve a complete combustion. Still furthermore, the buffer unit includes an exhaust-buffering mask and a fan therein, which can reduce the speed of the exhaust gas and achieve a uniform exhaust flow, so that the exhaust gas transferred back to the combustion unit can be reduced. Still furthermore, since the high-temperature exhaust gas can consume the soot accumulated in the filter unit, the regeneration process can be performed properly. The emission unit includes a porous tail pipe sealed with a porous cover, which can increase the speed of removing heat and eliminate the occurrence of sparks.

According to another feature of the present invention, the nozzle is provided in an open-end container that defines a plurality of through holes at its bottom, so that unburned fuel can flow out of the container via the through holes.

According to a further feature of the present invention, the exhaust-buffering mask has a conical wall that defines a plurality of through holes, so that the exhaust gas can go past the mask via the through holes to achieve the purpose of speed reduction.

Other objects, advantages, and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic view of an exhaust purification device for vehicles according to one embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

To allow those skilled in the art to implement the present invention easily, one embodiment is illustrated in detail in the following paragraphs with reference to the accompanying drawings.

Referring to FIG. 1, an exhaust purification device for vehicles according to one embodiment of the present invention is shown, which generally comprises a connection unit 1, a combustion unit 2, a buffer unit 3, a filtration unit 4, an emission unit 5, and a control unit 6.

The connection unit 1 can be formed as a pipe 11, which has an inlet 111 and an outlet 112, wherein the inlet 111 is adapted to be connected to an exhaust pipe of a vehicle's engine (not shown).

The combustion unit 2 includes a main housing 20, a fuel-atomization nozzle 23, and an igniter 24. The main housing 20 is connected to the outlet 112 of the connection unit 1. The main housing 20 defines a combustion chamber 200 therein and is provided therein with a protective shell 21 and an open-end container 22 at a location that is not aligned with the outlet 112 of the connection unit 112, so that the exhaust gas expelled from the outlet 112 would not be hindered by those structures. The open-end container 22 is located within the protective shell 21 and leaves a gap with the protective shell 21. The fuel-atomization nozzle 23 and the igniter 24 are arranged in the open-end container 22 and face towards the combustion chamber 200. The fuel-atomization nozzle 23 is connected to a fuel tank 25, which is located outside the main housing 20 and contains a fuel pump therein (not shown), via a tube that is provided with an electrical valve 251, such as a solenoid valve. An air pump 26 is connected to the open-end container 22 via a tube for pumping ambient air into the container 22. The igniter 24 is provided with insulators 241 which each is provided with a protective sleeve 242 for preventing soot accumulation.

The buffer unit 3 includes a first buffer zone 3A and a second buffer zone 3B communicating with the first buffer zone 3A. The first buffer zone 3A is connected to the main housing 20 of the combustion unit 2 and is provided therein with an exhaust-buffering mask 31 near the main housing 20 of the combustion unit 2 and a fan 32 near the second buffer zone 3B, so that the exhaust gas expelled from the combustion unit 2 can go past the exhaust-buffering mask 31 and then rotate the fan 32 to enter the second buffer zone 3B. The temperature sensor 7 is provided in the first buffer zone 3A of the buffer unit 3 for detecting temperature therein. Preferably, the exhaust-buffering mask 31 can be formed as a generally conic body, wherein it has a conical wall that defines a plurality of through holes 311, through which the exhaust gas can pass, and thus the flow speed of the exhaust gas can be achieved. The fan 32 has a central axle 321 mounted at a structure between the first buffer zone 3A and the second buffer zone 3B. As such, the exhaust gas can force the fan 32 to rotate and thus enter the second buffer zone 3B.

The filtration unit 4 is connected to the second buffer zone 3B of the buffer unit 3 for receiving exhaust gas therefrom. The filtration unit 4 is provided with a cellular-structure filter 41 therein.

The emission unit 5 is connected to the filtration unit 4. The emission unit 5 includes an L-shaped tail pipe 51 that has a porous pipe wall 511 and is sealed with a porous cover 52 at its outlet. The porous pipe 511 is referred as a pipe wall defining multiple tiny through holes or as a fine-mesh pipe wall. The porous cover 52 is referred as a cover defining multiple tiny through holes or as a fine-mesh cover.

The control unit 6, which is based on a microprocessor, is electrically connected with the igniter 24, the fuel pump of the fuel tank 25 (not shown), the air pump 26, and the temperature sensor 7 for controlling their operations. Furthermore, a battery or other backup power sources can be provided for the control unit 6, so that the control unit 6 can continue time-related operations when the vehicle is stopped. The control unit 6 can be set with various routines for a regeneration process. For example, the control unit 6 can be set with a daily regeneration count and a required operation time for extending the service life of the filter. Also, during regeneration, the combustion temperature and duration can be measured so that when the measured regeneration period reaches the setting value, the regeneration combustion can be stopped. For example, the control unit 6 can be set in a way that allows a vehicle to automatically perform a regeneration process at its daily first starting. For example, the control unit 6 can display information about the combustion temperature, the fuel supply, the initial time of a regeneration process, and the duration of the regeneration process. Also, the associated regeneration data can be recorded if necessary.

Normally, the combustion unit 2 is inactive when driving a vehicle. The exhaust gas from the exhaust pipe can sequentially flow through the combustion unit 2, the buffer unit 3, the filtration unit 4, and the emission unit 5, wherein the filtration unit 4 can be used to filter out the particulate matter contained in the exhaust gas, and the filtered exhaust gas can be expelled from the emission unit 5. After the vehicle has been driven for a period of time, the particulate matter contained in the exhaust gas may plug the cellular-structure filter 41, and the plugged filter would hinder the emission of the exhaust gas. To remove the plugged particulate matter, a regeneration process for the filter 41 can be manually initiated by a user or automatically initiated by the control unit 6, to allow the fuel pump of the fuel tank 25 to pump fuel to the electrical valve 251, which can be opened at a later time to allow the fuel-atomization nozzle 23 to spray fine drops of fuel, which can be ignited by the igniter 24 to start a combustion, so that the temperature in the combustion chamber 200 can be increased. At the same time, the air pump 26 can be started to pump ambient air into the open-end container 22 to allow the atomized fuel to be mixed with air at an optimum ratio of fuel to air for obtaining a complete combustion. The unburned fuel during the combustion can flow out of the open-end container 22 via the through holes 221 defined at the portion of the container. On the other hand, the burned high-temperature exhaust gas can go past the exhaust-buffering mask 31 via the through holes 311, thereby reducing the flow speed of the exhaust gas. Thereafter, the high-temperature exhaust gas can drive the fan 32 to rotate, thereby guiding the high-temperature exhaust gas to enter the second buffer zone 3B. As such, a uniform exhaust flow can be obtained, and the exhaust gas being transferred back to the combustion unit 2, which may blow out the burning flame therein, can be reduced. Thereafter, the high-temperature exhaust gas can flow through the filter unit 4 to consume the particulate matter plugged in the cellular-structure filter 41, thereby cleaning the filter. Thus, the exhaust gas can go past the cellular-structure filter 41 smoothly to enter the emission unit 5, at which the exhaust gas can be expelled to the environment. Additional advantages of the emission unit 5 are that the porous tail pipe 51 can facilitate the exhaust gas to be quickly and efficiently expelled to the environment; the porous cover 52 can eliminate the occurrence of sparks, which may occur at the outlet of the porous tail pipe 51.

In conclusion, the present invention has the following advantages:

1. The combustion unit 2 is connected to an engine's exhaust pipe through a connection unit 1 such that the exhaust gas expelled from the exhaust pipe would not be hindered by the nozzle structure provided in the combustion unit 2, so that the exhaust gas can be expelled more smoothly.

2. The air pump 26 allows the fuel spray from the nozzle 23 to be mixed adequate air to increase the combustion efficiency.

3. The buffer unit 3 employs the exhaust-buffering mask 31 and the fan 32 to reduce the flow speed of the exhaust gas and achieve a uniform exhaust gas. This can reduce the exhaust gas being transferred back to the combustion unit 2.

4. The high-temperature exhaust gas can effectively consume the soot accumulated in the filtration unit 4.

5. The emission unit 5 employs a porous tail pipe 51 sealed with a porous cover 52, which can increase the speed of removing heat and eliminate the occurrence of sparks.

Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure is made by way of example only and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention hereinafter claimed. 

I claim:
 1. An exhaust purification device for vehicles, comprising: a connection unit including an inlet and an outlet, the inlet adapted to be connected to an exhaust pipe of a vehicle's engine; a combustion unit including a main housing, a fuel-atomization nozzle, and an igniter, wherein the main housing is connected to the outlet of the connection unit, the main housing defining a combustion chamber therein and being provided therein with a protective shell and an open-end container at a location that is not aligned with the outlet of the connection unit, the open-end container being located within the protective shell and leaving a gap with the protective shell, the fuel-atomization nozzle and the igniter being arranged in the open-end container and facing towards the combustion chamber, the fuel-atomization nozzle being connected to a fuel tank containing a fuel pump via a tube being provided with an electrical valve, an air pump being connected to the open-end container, a buffer unit including a first buffer zone and a second buffer zone communicating with the first buffer zone, wherein the first buffer zone is connected to the main housing of the combustion unit and is provided therein with an exhaust-buffering mask near the main housing of the combustion unit and a fan near the second buffer zone to allow exhaust gas to go past the exhaust-buffering mask and then rotate the fan to enter the second buffer zone, whereby exhaust gas can flow into the second buffer zone more uniformly, thereby reducing exhaust gas being transferred back to the combustion unit; a filtration unit connected to the second buffer zone of the buffer unit for receiving exhaust gas therefrom; an emission unit connected to the filtration unit, wherein the emission unit includes an L-shaped tail pipe having a porous pipe wall and being sealed with a porous cover at its outlet; a temperature sensor provided in the first buffer zone of the buffer unit for detecting temperature therein; and a control unit electrically connected with the igniter, the fuel pump of the fuel tank, the air pump, and the temperature sensor for controlling their operations.
 2. The exhaust purification device for vehicles as claimed in claim 1, wherein the open-end container defines a plurality of through holes at its bottom.
 3. The exhaust purification device for vehicles as claimed in claim 1, wherein the exhaust-buffering mask has a conical wall that defines a plurality of through holes. 